I am having trouble introducing my welsh harlequin/pekin to my 5 mallards. My harlequin (I call her Harley) is incredibly kind and craves their attention, but the issue is that she is bigger than them. This intimidates the mallards and they gang up on her and start pecking her (sometimes pulling out feathers). I keep her in a cage next to the mallards' pin. This is the third day that she has been here and the only improvement made is that the mallards don't hiss at her anymore. Any suggestions?